Firearm Delay Mechanism

ABSTRACT

In some embodiments, a firearm comprises a lower receiver, a bolt carrier and a weight. The lower receiver is arranged to support a hammer and an auto-sear. The bolt carrier comprises a body and a striker moveable with respect to the body between a first position and a second position. The body defines a first cavity adjacent the striker. A weight is positioned in the first cavity and arranged to move the striker to the second position, wherein the striker is arranged to operate the auto-sear.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/923,341, filed Mar. 16, 2018, which claims the benefit of U.S. PatentApplication No. 62/472,043, filed Mar. 16, 2017, the entire contents ofeach are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

This invention relates to automatic machine guns and fire controlmechanisms.

Automatic repeating firearms generally have high firing rates. Forexample, M4 and M16 machine guns can fire 700-900 or more rounds perminute. While a high firing rate has certain benefits, there can bedrawbacks such as decreased accuracy and increased ammunitionconsumption.

There remains a need for firearm mechanisms having variable rates offire. There remains a need for novel firearm mechanisms. There remains aneed for mechanisms that can slow the firing rate of available automaticfirearms.

All US patents and applications and all other published documentsmentioned anywhere in this application are incorporated herein byreference in their entirety.

Without limiting the scope of the invention a brief summary of some ofthe claimed embodiments of the invention is set forth below. Additionaldetails of the summarized embodiments of the invention and/or additionalembodiments of the invention may be found in the Detailed Description ofthe Invention below.

A brief abstract of the technical disclosure in the specification isprovided as well only for the purposes of complying with 37 C.F.R. 1.72.The abstract is not intended to be used for interpreting the scope ofthe claims.

BRIEF SUMMARY OF THE INVENTION

In some embodiments, a firearm mechanism comprises a hammer, anauto-sear and a bolt carrier. The bolt carrier comprises a body and astriker moveable with respect to the body between a first position and asecond position. The striker is biased to the first position by abiasing mechanism. The striker does not contact the auto-sear in thefirst position. The striker contacts the auto-sear in the secondposition and is arranged to operate the auto-sear in the secondposition.

In some embodiments, the firearm mechanism comprises a reciprocatingweight arranged to move the striker to the second position. Desirably,the weight is moveable with respect to the bolt carrier and arranged tooperate the auto-sear.

In some embodiments, the firearm mechanism comprises a buffer comprisinga buffer cavity, the weight arranged to travel into the buffer cavity.

In some embodiments, a firearm comprises a lower receiver, a boltcarrier and a weight. The lower receiver is arranged to support a hammerand an auto-sear. The bolt carrier comprises a body and a strikermoveable with respect to the body between a first position and a secondposition. The body defines a first cavity adjacent the striker. A weightis positioned in the first cavity and arranged to move the striker tothe second position, wherein the striker is arranged to operate theauto-sear.

These and other embodiments which characterize the invention are pointedout with particularity in the claims annexed hereto and forming a parthereof. However, for a better understanding of the invention, itsadvantages and objectives obtained by its use, reference can be made tothe drawings which form a further part hereof and the accompanyingdescriptive matter, in which there are illustrated and described variousembodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of the invention is hereafter described withspecific reference being made to the drawings.

FIG. 1 shows an exploded view of an embodiment of a firearm delaymechanism.

FIG. 2 shows a cross-sectional view of a portion of a firearm comprisingan embodiment of a delay mechanism.

FIGS. 3-7 show the operation of an embodiment of a delay mechanismduring a firing sequence.

DETAILED DESCRIPTION OF THE INVENTION

While this invention may be embodied in many different forms, there aredescribed in detail herein specific embodiments of the invention. Thisdescription is an exemplification of the principles of the invention andis not intended to limit the invention to the particular embodimentsillustrated.

For the purposes of this disclosure, like reference numerals in thefigures shall refer to like features unless otherwise indicated.

FIG. 1 shows an embodiment of components that can be used in a firearmdelay mechanism 10. In some embodiments, the parts of the firearm delaymechanism 10 are suitable for use in standard M4 and M16 firearms asdrop-in replacement parts, without requiring any change to other partsof the firearm.

In some embodiments, a firearm delay mechanism 10 comprises a boltcarrier 30, a striker 42, at least one weight 44 and a buffer 50. Insome embodiments, the striker 42 is carried by the bolt carrier 30. Insome embodiments, the weight 44 is arranged to contact and move thestriker 42, and the striker 42 can be arranged to operate an auto-searof a firearm. In some embodiments, the buffer 50 comprises a cavity 52,and the weight(s) 44 can be oriented in the cavity 52.

FIG. 2 shows an embodiment of a firearm delay mechanism 10 positionedwith respect to an embodiment of a lower receiver 12. In someembodiments, the lower receiver 12 comprises a standard militaryspecification M4 or M16 lower receiver. In some embodiments, a lowerreceiver 12 comprises a hammer 14 and an auto-sear 16. In someembodiments, the hammer 14 comprises a sear 18 arranged to contact thesear of a finger trigger (not illustrated). In some embodiments, thehammer 14 and auto-sear 16 comprise standard military specificationparts.

In some embodiments, the striker 42 is moveable with respect to the boltcarrier 30 between first and second positions. In some embodiments, thestriker 42 is biased to the first position by a biasing mechanism 60. Insome embodiments, when the striker 42 is in its second position and thebolt carrier 30 is properly oriented with respect to the lower receiver12, the striker 42 will operate the auto-sear 16 and fire a round.

With reference to FIGS. 1 and 2, in some embodiments, the bolt carrier30 comprises a cavity 32. In some embodiments, the cavity 32 is open tothe rear end 38 of the bolt carrier 30. In some embodiments, the cavity32 of the bolt carrier 30 is aligned with the cavity 52 of the buffer50. In some embodiments, at least a portion of the weight 44 is arrangedto travel between the cavity 52 of the buffer 50 and the cavity 32 ofthe bolt carrier 30.

In various embodiments, the weight 44 can have any suitable size, shapeand configuration. A weight 44 having a shorter length can take moretime to traverse the path from a rear of the buffer cavity 52 to thestriker 42 than a weight 44 having a longer length. A weight 44 orassembly of weights 44 can occupy any suitable length portion of thebuffer cavity 52 and/or the bolt carrier cavity 32. Weights 44 ofdifferent sizes can be used to adjust the specific timing delay of thedelay mechanism 10.

A weight 44 can comprise any suitable material or combination ofmaterials, such as metals, polymers, composite materials, etc. In someembodiments, a weight 44 comprises aluminum. In some embodiments, aweight 44 comprises steel. In some embodiments, a weight 44 comprisestungsten. Varying the mass of a weight 44 can change the time delayprovided by the delay mechanism 10.

In some embodiments, a weight 44 is free-floating and free to move inresponse to applied forces.

In some embodiments, a weight 44 comprises an assembly having aplurality of weight portions 70, 72. Any suitable number of weightportions 70, 72 can be used, and weight portions 70, 72 can be similarto one another or different in size, shape, material, etc. In someembodiments, a weight 44 comprises one or more spacers 45, which can beused between adjacent weight portions 70, 72. In some embodiments, aspacer 45 comprises a bumper. In some embodiments, a spacer 45 comprisesa polymeric or elastomeric material. In some embodiments, a spacer 45 isattached to one or more of the weight portions 70, 72. For example, insome embodiments, a spacer 45 comprises a stem 41 arranged to engage acavity 40 formed in a weight portion 70, 72.

In some embodiments, the rear end 38 of the bolt carrier 30 and thefront end 54 of the buffer 50 are arranged to engage one another andself-align. In some embodiments, the front end 54 of the buffer 50comprises an inclined surface, peak or frustoconical surface 56 arrangedto engage a complimentary shaped declined surface, valley or inversefrustoconical surface of the rear end 38 of the bolt carrier 30. Thecomplimentary shaped ends 38, 54 desirably encourage the bolt carrier 30and buffer 50 to align such that a central axis of the cavity 32 of thebolt carrier 30 is coaxial with a central axis of the cavity 52 of thebuffer 50.

In some embodiments, the rear end 38 of the bolt carrier 30 ischamfered.

In some embodiments, the front end 52 of the buffer 50 is chamfered.Chamfers can help the weight(s) 44 to pass smoothly across thetransition between the bolt carrier cavity 32 and the buffer cavity 52.

In some embodiments, the buffer 50 comprises a bumper 58. In someembodiments, the bumper 58 is attached to the buffer 50 with a pin 59.In some embodiments, the bumper 58 comprises a contacting surface 64arranged to contact the weight 44.

In some embodiments, the striker 42 is positioned at an end of the boltcarrier cavity 32, and the weight 44 can contact the striker 42.

In some embodiments, the bolt carrier 30 comprises a cavity 34 and aslot 35 arranged to support striker components. In some embodiments, astriker pin 46 is received in the cavity 34 and arranged to engage thestriker 42. In some embodiments, an engaging portion 47 of the strikerpin 46 is received in an aperture 43 in the striker 42.

In some embodiments, the biasing mechanism 60 comprises a coil spring 62extending around the striker pin 46. In some embodiments, the strikerpin 46 comprises a flange 48 arranged to engage the biasing mechanism60. In some embodiments, the biasing mechanism 60 and striker pin 46 canbe installed in the cavity 34, the biasing mechanism 60 can becompressed, and the striker 42 installed in the slot 35, wherein theengaging portion 47 of the striker pin 46 can engage the striker 42. Thebiasing mechanism 60 and striker pin 46 can bias the striker 42 againsta flange 36 of the bolt carrier 30. In some embodiments, the striker 42abuts the flange 36 when the striker 42 is in the first position withrespect to the bolt carrier 30.

FIG. 3 illustrates an embodiment of a delay mechanism 10 at a point intime after a first round has been fired. The bolt carrier 30 and buffer50 are traveling in the rearward direction 79, for example under theforce of expanding gasses from the first round. The weight(s) 44 arefree to move within the cavities 32, 52. As the bolt carrier 30 moves inthe rearward direction 79, the weight(s) 44 reach a forward end of thebolt carrier cavity 32, for example contacting the striker 42, and thenmove in the rearward direction 79 along with the bolt carrier 30.

As the bolt carrier 30 and buffer 50 reach the end of their rearwardtravel, they will decelerate and stop, for example under the force of arecoil spring (not illustrated). During deceleration, the weight(s) 44will continue traveling in the rearward direction 79 and will move withrespect to the cavities 32, 52. In some embodiments, the weight(s) 44will exit the bolt carrier cavity 32 and move entirely into the buffercavity 52. In some embodiments, the weight(s) 44 will travel untilstopping at the rear of the buffer cavity 52, for example with arearmost weight 44 contacting the bumper 58.

FIG. 4 shows the weight(s) 44 stopped against the bumper 58. The boltcarrier 30 and buffer 50 are being moved in the forward direction 78,for example under the force of a recoil spring (not illustrated). Thebolt carrier 30 and buffer 50 will typically move forward until reachingtheir forward stop positions.

FIG. 5 shows the bolt carrier 30 and buffer 50 reaching their forwardpositions with respect to the lower receiver 12, a time when a standardmil-spec M16 may fire a second round; however, the delay mechanism 10does not yet fire. Due to positioning of the bolt carrier 30, thestriker 42 is positioned near the auto-sear 16 but does not contact theauto-sear 16. The striker 42 remains biased to its first position withrespect to the bolt carrier 30 by the biasing mechanism 60. Theweight(s) 44 are still shown near the rear of the buffer cavity 52 buthave begun traveling forward 78 in the buffer cavity 52.

FIG. 6 shows the weight(s) 44 traveling forward 78 in the cavities 32,52. In some embodiments, the weight(s) 44 will pass entirely into thebuffer cavity 32.

FIG. 7 shows the weight(s) 44 impacting the striker 42 and operating thestriker 42, moving the striker 42 to its second position with respect tothe bolt carrier 30. In the second position, the striker 42 contacts andoperates the auto-sear 16, releasing the hammer 14 and firing anotherround.

A firearm comprising a delay mechanism 10 can fire more slowly in afully automatic firing mode than a traditional version of the firearm.The travel of the weight(s) 44 provides a time delay in the cyclingrate, and different embodiments of weight(s) 44 can provide differentadjustments in cycle rate. In some embodiments, the size and physicaldimensions of a weight 44 can be adjusted to vary the cycle rate.Different numbers of weights 44 can be used to vary the cycle rate.Different materials and weights 44 having different masses can be usedto vary the cycle rate. In some embodiments, substituting a buffer 50having a different size, which can provide a buffer cavity 52 having adifferent length, can adjust the cycle rate. In some embodiments,changing a length of a bumper 58 can change the length of the buffercavity 52 and can adjust the cycle rate.

In some embodiments, the weight(s) 44 deliver energy to the bolt carrier30 upon impact with the striker 42, for example placing an impact forceon the bolt carrier 30 in the forward direction 78. In some embodiments,the weight(s) 44 can drive the bolt carrier assembly into battery, forexample in the event that the bolt carrier assembly does not fullyassume its configuration in battery under force from a recoil spring.Thus, in some embodiments, the weight(s) 44 can be arranged to performall functions of traditional buffer weights.

The above disclosure is intended to be illustrative and not exhaustive.This description will suggest many variations and alternatives to one ofordinary skill in this field of art. All these alternatives andvariations are intended to be included within the scope of the claimswhere the term “comprising” means “including, but not limited to.” Thosefamiliar with the art may recognize other equivalents to the specificembodiments described herein which equivalents are also intended to beencompassed by the claims.

Further, the particular features presented in the dependent claims canbe combined with each other in other manners within the scope of theinvention such that the invention should be recognized as alsospecifically directed to other embodiments having any other possiblecombination of the features of the dependent claims. For instance, forpurposes of claim publication, any dependent claim which follows shouldbe taken as alternatively written in a multiple dependent form from allprior claims which possess all antecedents referenced in such dependentclaim if such multiple dependent format is an accepted format within thejurisdiction (e.g. each claim depending directly from claim 1 should bealternatively taken as depending from all previous claims). Injurisdictions where multiple dependent claim formats are restricted, thefollowing dependent claims should each be also taken as alternativelywritten in each singly dependent claim format which creates a dependencyfrom a prior antecedent-possessing claim other than the specific claimlisted in such dependent claim below.

This completes the description of the preferred and alternateembodiments of the invention. Those skilled in the art may recognizeother equivalents to the specific embodiment described herein whichequivalents are intended to be encompassed by the claims attachedhereto.

1. A firearm mechanism comprising: a hammer; an auto-sear; a boltcarrier comprising a body and a striker moveable with respect to thebody between a first position and a second position, the striker biasedto the first position by a biasing mechanism; the striker not contactingthe auto-sear in the first position, the striker contacting theauto-sear in the second position.
 2. The firearm mechanism of claim 1,comprising a reciprocating weight arranged to move the striker to thesecond position.
 3. The firearm mechanism of claim 1, comprising a pinsupported by the bolt carrier, the striker comprising an aperture, aportion of the pin oriented in the aperture.
 4. The firearm mechanism ofclaim 3, the biasing mechanism comprising a spring arranged to contactthe pin.
 5. The firearm mechanism of claim 1, the bolt carrier bodydefining a cavity adjacent to the striker.
 6. The firearm mechanism ofclaim 5, the striker comprising a wall portion of the cavity.
 7. Thefirearm mechanism of claim 5, comprising a weight, the weight moveablewith respect to the bolt carrier, the weight arranged to operate theauto-sear.
 8. The firearm mechanism of claim 7, comprising a bufferadjacent to the bolt carrier, the buffer comprising a buffer cavity, thefirearm mechanism comprising an orientation wherein the weight is in thebuffer cavity.
 9. The firearm mechanism of claim 8, wherein the weighttravels between the cavity and the buffer cavity during a firing cycle.10. The firearm mechanism of claim 8, wherein surfaces of the boltcarrier and buffer that contact one another comprise complimentaryshapes arranged to self-align the bolt carrier and buffer on a commonaxis.
 11. The firearm mechanism of claim 8, wherein one of the boltcarrier and buffer comprises an inclined surface, and the other of thebolt carrier and buffer comprises a declined surface, the inclinedsurface arranged to contact the declined surface.
 12. The firearmmechanism of claim 11, wherein the inclined surface contacts thedeclined surface when a central axis of the bolt carrier and a centralaxis of the buffer are coaxial.
 13. The firearm mechanism of claim 8,the buffer comprising a front aperture and a rear bumper.
 14. A firearmcomprising: a lower receiver arranged to support a hammer and anauto-sear; a bolt carrier comprising a body and a striker moveable withrespect to the body between a first position and a second position, thebody defining a first cavity adjacent the striker; a weight positionedin the first cavity, the weight arranged to move the striker to thesecond position, the striker arranged to operate the auto-sear in thesecond position.
 15. The firearm of claim 14, the striker biased to thefirst position by a biasing mechanism.
 16. The firearm of claim 14,comprising a buffer adjacent to the bolt carrier, the buffer comprisinga second cavity, the weight arranged to travel between the first cavityand the second cavity.
 17. The firearm of claim 16, the bolt carriercomprising an opening into the first cavity and the buffer comprising anopening into the second cavity.